Cover
Vol. 16 No. 2 (2025)

Published: December 15, 2025

Pages: 87-101

Research Paper

Numerical and Experimental Investigations on Hydrothermal Characteristics of Turbulent Flow in Channel with Circular Turbulators

Albashir A. Obeid 1 M. A. Ahmed Mohd Zamri Yusoff 2
1Department of Mechanical Engineering, College of Engineering, University of Anbar, Ramadi, 31001, Anbar, Iraq.
2Department of Mechanical Engineering, Universiti Tenaga Nasional, Kajang, Selangor, Malaysia, TNB Research Sdn. Bhd., Kajang, Selangor
History
  • Received: July 3, 2025
  • Revised: October 12, 2025
  • Accepted: November 19, 2025
  • Available Online: December 15, 2025
DOI

https://doi.org/10.37649/AJES-25-006

Abstract

In this study, turbulent flow and heat transfer in a two-dimensional channel equipped with adiabatic circular turbulators were investigated both experimentally and numerically for Reynolds numbers of 2000, 3000, 4000, and 5000. Three turbulator configurations were considered, involving one, two, and three identical turbulators, each with a diameter of $D=3$ mm and a uniform spacing of $SL=30$ mm, positioned at the channel centerline. The governing continuity, momentum, and energy equations were discretized using the finite volume method and solved iteratively using the SIMPLE algorithm. Turbulence effects were modeled using the low-Reynolds-number k-ε turbulence model. The influence of Reynolds number and turbulator count on the friction factor, average Nusselt number, entropy generation, and hydrothermal performance factor was analyzed. Results revealed that increasing the number of turbulators significantly enhances heat transfer and alters flow behavior. Both the average Nusselt number, friction factor, and entropy generation increased with turbulator number. The configuration with three turbulators demonstrated the highest hydrothermal performance, achieving a maximum performance factor of approximately 1.58 at $Re=2000$. The numerical results showed good agreement with experimental data, which also employed varying numbers of circular turbulators.

Keywords

References

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